Speed control mechanism



July 27, 1965 .1. FULLER SPEED CONTROL MECHANISM 5 Sheets-Sheet 1Original Filed Oct. 2, 1961 N OE Null.

INVENTOR. JOHN L. FULLER ATTORNEY y 1965 J. L. FULLER 3,196,973

SPEED CONTROL MECHANISM Original Filed Oct. 2, 1961 5 Sheets-Sheet 2 AFIG. 4

\ INVENTOR.

8 JOHN L. FULLER FIG. 6 BY ATTORNEY July 27, 1965 J. L. FULLER 3,196,973

SPEED CONTROL MECHANISM Original Filed Oct. 2, 1961 5 Sheets-Sheet 3FIG. 7

INVENTOR.

JOHN L. FULLER ATTORNEY July 27, 1965 J. FULLER 3,196,973

SPEED CONTROL MECHANISM Original Filed Oct. 2, 1961 5 Sheets-Sheet 4FIG. 8

INVENTOR.

JOHN L. FULLER ATTOR N EY July 27, 1965 TRANSMISSION J. L. FULLER SPEEDCONTROL MECHANISM Original Filed Oct. 2, 1961 5 Sheets-Sheet 5 FIG. I I

p/ F I6 I 2 INVENTOR- JOHN L. FULLER ATTORNEY United States Patent3,196,973 SPEED CONTROL MECHANISM John L. Fuller, 802 St. Clair Ava,Shaker Heights, Ohio Continuation of application er. No. 142,265, Oct.2, 1961. This application May 4, 1964, Ser. No. 365,855 Claims. '(Cl.180-821) This invention pertains to the art of speed governors, and moreparticularly to a speed governor for variable speed power sources.

This application is a continuation application of my copendingapplication Serial No. 142,265, filed October 2, 1961, and nowforfeited.

The invention is particularly applicable to governing of the speed of amotor vehicle and will be described with particular reference thereto,although it will be appreciated that the invention has broaderapplications and may be used to govern speed of any type of rotatingpower sources such as Diesel or gasoline engines, either fixed ormovable, and variable speed electric motors.

In the art of governing the speed of motor vehicles, it has been knownto provide a servo-motor which opens and closes the throttle setting ofthe engine and to power this servo-motor with the vacuum of the manifoldthrough a speed sensitive valve or pressure modulator. Such valvesnormally comprise a rotating member which changes position in responseto centrifugal force. This change in position is then translated to thevalve itself. In all of such prior installations, difliculty has existedin obtaining satisfatcory operation because of the inherent frictionbetween the various parts of the valves as they move under the effectsof the centrifugal force. This has resulted in either erratic operationor in hunting as the governor seeks to control the speed of the vehicleto a preset speed.

It has heretofore been proposed to provide a pressuremodulating valvehaving a valve member which moves in friction-free relationship to aspaced member, but difliculty has been experienced with sucharrangements because variations in the manifold pressure resulted in avariable force on the member in addition to the centrifugal force whichresults in erratic and unsatisfactory performance. Various means havebeen provided to compensate for this effect, but heretofore these meanshave been unsuccessful.

Another problem with speed governors for motor ve hicles has been thatof deactivating the control of the governor when the vehicle is stoppedor when the speed of the vehicle is substantially different from that ofthe set speed of the governor. Thus, if the set speed of the governorwere miles per hour, or even 10 miles per hour, and the vehicle enginewas initially started with the vehicle at rest and the engine disengagedfrom the rear wheels, the governor would immediately indicate a need formaximum power from the engine which could result in a? destructiveoverspeeding of the engine.

The present invention contemplates an improved speed control pressuremodulating valve which overcomes all of the above-referred todifi'iculties and others and provides a valve arrangement which issimple in construction, economical to manufacture, and which gives ahighly improved performance characteristic.

In accordance with the present invention, a speed sensitive valve isprovided of a base member and a rotatable valve member, each havingported surfaces substantially perpendicular'to the axis of rotation andin close but spaced relationship, the valve member having a center ofgravity offset from the axis of rotation and being biased toward theaxis, whereby as it rotates, it is radially displaced from the axis'ofrotation to move the ports into and out of alignment. One of the portsleads to a pressure source and the other port leads to the servomotorsuch that relative alignment of these ports controls the pressure in theservo-motor.

Further in accordance with the present invention, means are provided forventing the servo-motor to atmosphere when the vehicle is at rest orwhen the vehicle is moving at a speed substantially different'from theset speed of the governor to thereby deactivate the servo-motor.

Further in accordance with the invention, the valve member is supportedfor rotation and radial displacement on the end of a swingablenon-extensible arm, which arm extends generally parallel to the axis ofrotation. With this arrangement, a variable vacuum or a pressure in thecontrol system does not create a variable radial force on the valvemember in addition to the centrifugal force thereon. I

Further in accordance with the invention, the surface. of the basemember has a pair of spaced ports, one communicated to the pressuresource and the other communicated with the servo-motor and the rotatableand axially displaceable valve member has a port in its surface tocontrol the amount of communication between the two ports in the surfaceof the base member.

The primary object of this invention is to provide a speed controlmechanism wherein a novel speed respon sive pressure modulator has afriction-free valving arrangement.

Another object of this invention is to provide such a speed controlmechanism to control the engine of a motor vehicle that is to travel ata substantially constant, desired speed regardless of variations inforces opposing such constant speed travel.

Another object of this invention is to provide a speed control mechanismwhich may be conveniently and readie ly attached to all types ofadjustable speed power sources for regulating the power control means ofthe power source to thereby maintain a predetermined, adjustable andconstant speed of operation. 1 7 Another object of this invention istoprovide a speed responsive pressure modulating valve for controllingthe speedof a power source which is not activated until the speed of thepower source is close to, but below, the set speed of the valve. I

A still further object of this invention is to provide a friction-freepressure modulating valve for controlling the speed of a power sourcesuch as an internalcombustion engine of a motor vehicle wherein thepressure of the control fluid is exerted substantially perpendicularlytothe movement of the valve members to thereby eliminate the effect ofvariations in the pressure of the control fluid on the operation of thefriction-free valve. I

.Still a further object of this invention is to'provide a friction-freevalve for modulating the pressure of a fluid which controls a throttlevalve of an internal combustion engine through the use of two relativelymovable valve members, one being radially fixed and having a controlport and the other being rotatable, radially movable and having acontrol port which moves into and out of alignment with the other tothereby modulate the pressure of the control fluid.

These and other objects and advantages will become apparent from thefollowing description used in illustrating the preferred embodiment ofthe invention as read in connection with the accompanying drawings inwhich:

FIGURE 1 is a sectional side elevation disclosing one embodiment of thenovel speed control mechanism;

FIGURE 2 is a partial cross-sectional view taken along line 2-2 ofFIGURE 1;

FIGURE 3 is a partial cross-sectional view taken along line 33 of FIGURE1;

FIGURE 4 is a top view of the speed control mechanism shown in FIGURE 1;

FIGURE 4a is a partial view disclosing the mounting arrangement for thecontrol spring; FIGURE 5 is a partial cross-sectional view taken alongline 5-5 of FIGURE 1;

FIGURE 6 is a partial cross-sectional view taken along line 6-6 ofFIGURE 1;

FIGURE 7 is a cross-sectional side elevation showing a second embodimentof the novel speed control mechanism;

FIGURE 8 is a partial cross-sectional view taken along line 8-8 ofFIGURE 7; 7

FIGURE 9 is a cross-sectional view taken along line 99 of FIGURE 7;FIGURE 10 is a cross-sectional view showing the modulating valve in thecontrol position;

FIGURE 11 is a cross-sectional view along line 11-11 of FIGURE 7; and IFIGURE 12 is a diagrammatical view of the speed control mechanism as itis incorporated within a vehicle. Referring now to the drawings, whereinthe showings are for the purpose of illustrating preferred embodimentsof the invention and not for limiting same, FIG- URE 1 discloses oneembodiment of the novel speed control mechanism comprising a stationaryframe A and a rotating pressure modulator B that is rotated inaccordance with the speed of an engine driven vehicle. The speed controlmechanism is used to modulate the pressure of a fluid which operates aservo-motor to vary the throttle setting of the vehicle engine.Basically, the stationary frame A comprises two spaced end plates 2, 4that are secured in spacedrelationship by tie rods 6, 8 which tie rodsare adjustably secured within the end plates 2,4 so that thedistancebetween the end plates is adjustable. Referring now to end plate2, there is proyided within the end plate an inlet manifold 10 which isclosedby a flanged cap 11. Motivating fluid having a pressure eitherabove or below atmospheric is introduced intothe manifold 10 through aninlet tube 9. To allow rotation of the pressure modulating structure B,end plate 2 is provided with a bearing sleeve 13 which extends into theflanged cap 11 to rotatably receive an input shaft 14 which is driven inaccordance with the vehicle speed by a conventional motion transmittingdevice which is not disclosed. To impart rotation to the structure B,the

input shaft 14 has its rearwardly extending end securely fastened to abase member 15-which really rotates about an axis substantiallycoinciding with its center of gravity.

Referring now to-the second end plate 4, an outlet manifold 17 beingclosed by flanged cap 18 directs fluid having a modulated pressure frommanifold 17 through an outlet tube 16. Thus the fluid operates aservo-motor which controls the throttle valve of the vehicle engine.This throttle controlling feature will-be discussed in detail later inthis specification. A bearing sleeve 20 is positioned within both theend plate 4 and the flanged cap 18 to rotatably receivaan output shaft21. Thus, the shafts 14 and 21 are journaled within the end plates 2, 4to allow rotation of the modulating structure as a unit. External threadsurfaces 12,. 19 on the flanged caps facilitate connection of thedriving devices to the rotating structure.

The bearing sleeves 13, 20 are suitably apertured to communicate themanifolds 10 and 17 with internal passages 22 and 42 of the rotatingshafts 14 and 21. This a rotating radially fixed base member 15 androtating radially displaceable valve member 30. The radially fixed basemember 15 has an internal chamber 23 and face plate 24 provided with aport which may be in the form of a slot 25 which is substantiallyaligned with the rotational axis x. Unmodulated fluid from passage 22enters chamber 23 and passes from the base member 15 through the port 25provided in the face plate 24. Since the valve member is radiallydisplaceabl-e, the base member 15 is provided with an inner adjustablestop 26 and an outer adjustable stop 27 to prevent excessive radialdisplacement of the valve member 30 in either direction. This'is bestshown in FIGURE 1. A vent port 29 extends transversely across face plate24 for a purpose to be hereinafter described in detail.

The valve member has a surface close to, but spaced from, the surface offace plate 24 during its radially outward movement. A port which may bein the form of a slot 31 in the front surface of valve member 30registers with port'25 to communicate the chamber 23 in base member 15with a chamber 32 in valve member 30. The chamber 32 is closed by aplate 33 having a rearwardly extending tube 34 and adjustable weights 35which weights may be stationary. The center of gravity of valve member30 is offset from the axis x about which the modulating structure Brotates. Thus, as the structure B rotates,

' the valve member 30 having a central axis y which is initially'alignedwith axis x, shifts radially outwardly to restrict the communicationbetween ports 25 and 31.

Thus, as the speed of the structure-B increases, the communicationbetween the chambers 23 and 32 is limited. By this arrangement, thepressure of the fluid Within chamber 32 is modulated according to therotational speed of the structure B. The phrase close to, but spacedfrom indicates that the valve member and base member are spaced fromeach other at all times. It is contemplated to vary the spacing asdesired so long as the minimum spacing does not allow the surfaces ofthe members to contact one another and the maximum spacing allowscontrol between ports 25 and 31. The usual rangeof spacing is .001 to.025 inch and in the preferred embodiment a spacing of approximately.005 is used.

A flexible tube 36 connects tube 34 to a sleeve 40 which extendsinwardly of the shaft 21. The flexible tube 36 allows movement of thevalve member 30 and may be constructed in any suitable manner; however,it is found that a. flexible rubber hose performs satisfactorily. Inpractice, the flexible tube 36 may consist of a metallic tube with aresilient bellows structure to allow radial movement of valve member 30.

The valve member 30 as it shifts radially with respect to face plate 24must remain spaced from the face plate, for if there is contact betweenthe face plate and the valve member 30, there Will be substantialfrictional forces developed to distract from the smooth operation ofthe. modulating valve. As the rotational speed of valve member 3t)increases, the valve member tends to shift radially outwardly withrespect to the base member under the influence of centrifugal force.This centrifugal force is yieldingly opposed by a force tending to biasthe valve member to its normal position with ports 25 and 31 aligned.This biasing force can be produced by a variety of means such as a coilspring mounted transversely of the valve member, one or more cantileversprings extending substantially parallel to theaxis of rotation, orother resilient means such as air cushions mounted to yieldingly resistmovement of the valve member. However, in the preferred embodiment apair of cantilever springs is provided to furnish not only the resilientmeans, but also the supporting means to prevent contact of the valvemember and base member.

In the preferred embodiment, the mounting means for the valve member 39comprises a pair of cantilever control springs 54, 55 mounted at one endon a spring piate 44 which plate is affixed to shaft 21 in abuttingrelationship With a shoulder 41 provided on rearwardly extending sleeve48. One cantilever control spring may be used instead of two controlsprings as shown in the present embodiment, however, it would then benecessary to contour the ported surfaces of face plate 24 and valvemember 34) to maintain a slight spacing between these surfaces as thevalve member shifts in an arcuate path. As is seen in FIGURE 4, the basemember 15 is aflixed to spring plate 44 by generally parallel driveshafts 45, 46 which forms the primary support for the structure B tothus allow the structure and its various component parts to rotate as aunit.

To allow adjustment of the speed setting of the modulating structure, anadjusting spring 50 extends from the spring plate 44 to the valve member30. This adjusting spring operates with the control springs to determinethe amount of centrifugal force required to displace the valve member acertain distance.

The inwardly facing surface of spring plate 44 receives an adjustablemounting lug 48 to secure the adjusting spring 56 onto the spring plate.Control spring 54 is joined through plate 54b to an adjustable mountinglug 52 which in turn has an elongated slot 52a to allow longitudinaladjustment of the spring 54. This adjusting feature is disclosed inFIGURE 4a. The forward end of the control spring 54 terminates in anangled portion 54a aflixed at the rear of plate 33 to control themovement of the valve member 39. The control spring 55 is mounted on thespring plate 44 in the same manner as control spring 54 and the forwardend of control spring 55 is secured to the under surface of the valvemember 30 so the control springs are substantially parallel. Thus, thecontrol springs form a parallelogram linkage system to guide themovement of the valve member 39 as it shifts radially with respect tothe base member 15. The forward end of adjusting spring 50 has adepending finger received within a slot 56 on the upper surface of thevalve member. This slot 56 is substantially wider than the diameter ofthe control spring 54 to allow engagement of the control spring with thevalve member without causing interference with the spacing of the valvemember from the face plate 24. To provide smoother contact between thevalve member 36 and the adjusting spring 50, the lower end of theadjusting spring can be rounded to form a spherical tip as shown inFIGURE 2.

The springs 5t), 54 and 55 are radially adjustable to give the propermovement of the valve member 30 with respect to the face plate 24 asshown in FIGURE 5 wherein upper radially extending parallel slots 52bprovide for adjustment of mounting lugs 48 and 52. and lower parallelslots 53b provide for adjustment of mounting lug 53. It is, of course,realized that the various adjusting features disclosed may be eliminatedor may be modified as long as they provide a substantial anchorage forthe adjusting spring and control springs.

To adjust the controlled speed, a novel device is used to shift thefulcrum of spring 56. A fulcrum plate 60 which rotates with themodulating structure B is provided with openings 63, 6d surroundingdrive shafts 45, 46 to hold the fulcrum plate onto the rotatingstructure B. The plate 66 has a central opening 61 which is symmetricalwith respect to the center of rotation of the fulcrum plate so that nodynamic unbalance will result as the plate rotates. The fulcrum platearrangement is best seen in FIGURE 3 showing a substantially flatsurface 62 which contacts adjusting spring 50 so that longitudinalmovement of the fulcrum plate 69 changes the force exerted by spring 50on the upper portion of the valve member 30. The control springs 5d, 55and the flexible tube 36 pass through the opening 61; therefore,longitudinal movement of the fulcrum plate will not interfere with theaction of the control springs. To move the fulcrum plate longitudinallyalong the adjusting spring 56, a pair of adjusting blocks 65, 66 areslidably received on the tie rods 6, 8 respectively. The inwardlyextending ends of the adjusting blocks 65, 66 have a slot which receivesthe fulcrum plate 60 to allow movement of the plate as the adjustingblocks are moved along the tie rods. The fulcrum plate may rotate withrespect to the adjusting blocks since there is no fixed connectionbetween these members. Links 67, 68 extending from the adjusting blocks65, 66 pass through end plate 4 and are secured to adjusting plate 69.Thus, reciprocal movement of the adjusting plate 69 causes movement ofthe adjusting blocks. The adjusting plate 69 may be appropriatelyapertured as at 70 in FIG- URE 6 so outlet tube 16 and shaft 21 may beconnected to their respective external members without interference fromthe adjusting plate 69.

In operation, the speed control mechanism is connected to a source ofpressurized fluid so that the speed control mechanism Will modulate thepressure of the fluid in accordance with the vehicle speed. The fluid,having a modulated pressure, then controls a servo-motor to operate thethrottle valve of an engine so the speed of the vehicle is maintainedsubstantially constant. The fluid enters inlet tube 9 and passes intochamber 23 through bearing sleeve 13 and passage 22. Then the fluid inchamber 23 passes outwardly through port 25 to the chamber 32 by way ofport 31. Thus, the alignment of port 25 and port 31 provides directcommunication between chambers 23 and 32. The fluid in chamber 32, whichhas a modulated pressure, passes through flexible tube 36 to the outlettube 16. It is noted that since a vacuum source is preferred, thecontrol fluid may actually flow from the outlet tube 16 toward the inlettube 9; however, the description of the direction of flow of thepressurized fluid is not to be taken as a limitation of the invention.The direction of flow is only illustrative and may be varied accordingto the pressure of the control fluid source. The base member 15 and thevalve member 30 rotate with the structure B in accordance with thevehicle road speed. Referring now to FIGURE 1, base member 15 rotatesabout axis x which passes through the port 25. The axis y of theradially displaceable valve member 30 passes through port 31 and issubstantially aligned with the axis x during relatively low rotationalspeed of the structure B. Since the center of gravity of the valve head30 is offset from axis x, as the speed of the structure B increases,axis y of valve member 30 is shifted outwardly with respect to axis x.This outward movement is against the resilient forces of springs 50, 54-and 55. As the axes x and y are displaced, the communication betweenchambers 23 and 32 is correspondingly restricted. Thus, the pressure inchamber 32 is varied to cause a corresponding change in the throttlesetting of the engine. It is of considerable importance that the valvemember 3t), as it moves radially with respect to the face plate 24, doesnot contact the face plate 24. Thus, the relative movement between ports25 and 31 is friction-free. If there were contact between valve member30 and face plate 24, it would be necessary to build up a certain amountof force to overcome the static friction between the contacting members.This build up of force causes an abrupt movement between the members andresults in an erroneous modulation between the chambers 23 and 32 toseriously limit the function of the speed control mechanism.

As the valve member 30 moves radially with respect to the face plate 24,there should be no contact; however, these members should be very closetogether to limit the pressure leak between the two members. Thus, it isdesired to provide substantially parallel movement between the valvemember 30 and the face plate 24. To accomplish this, variousarrangements may be used; but in the embodiment shown a pair of controlsprings 54, 55 are secured to the spring plate 44 and the valve member30 to form a parallelogram linkage. Thus, the radial movement of thevalve member 30 against the resiliency of the con trol springs 54, 55 issubstantially parallel to the surface of the face plate 24. To align theports 25 and 31 and to impart the proper movement of valve member 30with respect to face plate 24, the control springs are adjust ablymounted onto the spring plate 44. The radial movement of the valvemember is limited by the adjustable stop 26 and 27. A' swingable,non-extensible link or arm could be used to support the valve memberclose to, but spaced from, the face plate; however, in such a structurethe mating surfaces should be contoured and an auxiliary spring meansmust be used to bias the valve member into the normal position. Bysupporting the valve member as in the preferred embodiment or as in thementioned alternative structure, the valve member does not move axially.The force of the pressure fluid on the valve member is axial and actsagainst the supports for the valve member so that it in no way afliectthe radial force on the valve member. For this reason, variations in theunmodulated fluid pressure do not change the operational characteristicsof the valve.

To change the speed setting of the speed control mechanism, theadjusting plate 69 is reciprocated longitudinally to change the positionof adjusting blocks 65, 66. This action shifts the location of fulcrumplate 60 and changes the resilient characteristics of adjusting spring59 which acts upon the upper surface of valve member 30 to adjust thespeed setting of the mechanism.

Means are provided for venting the servo-motor to atmosphere when thevehicle is at rest or when the vehicle is moving at a speedsubstantially below the set speed of the governor to thereby deactivatethe servo-motor. This means prevents over-speeding of the vehicle if thegovernor is in operation and the engine is disconnected from the rearwheels. Many structural-embodiments may be used; however, in thepreferred embodiment the vent port 29 in the outer surface of face plate24 is arranged to communicate with slot 31 to vent chamber 32 to theatmosphere when the speed of the rotating structure B is below the speedof the governor. This causes control of the vehicle only above a setvalue at which time the vent port 29 is out'of communication with theslot 31.

' Referring now to FIGURE 7, a modification of the invention isdisclosed wherein the stationary frame A comprises spaced end plates162, 164 secured together by tie rods 1196, 108 and having manifolds110, 117 covered by flanged caps 111, 113 provided with an inlet tube109 and an outlet tube 116. same as it is found in the previouslydiscussed embodiment of the invention. Fluid having unmodulated pressureenters inlet tube 109 and passes through a bearing sleeve 113 to achamber 123 centrally located within a base member 115 as is shown inFIGURE 8. The base member 115 rotates about axis x and is driven by aninput shaft 114. A second chamber 123a is provided within the basemember 115 and the two chambers within the base member'are closed by aface plate 124 which has a slot 125 opening into chamber 123 and a slot126 opening into chamber 123a. The chambers 123 and 123a are not indirect communication with each other. The outer surface of face plate124 has an external contoured surface 12451 and a transversely.extending vent slct'127.

To control the communication between chamber 123 and chamber 123a sothat fluid in the latter chamber has a modulated pressure, a valvemember 13f) moves radially with respect to the face plate 124 in closerelationship to the external surface 124a without actually coming intocontact with this surface. The outer surface of the valve member 139 hasa contoured surface 130a which substantially matchesthe externalcontoured surface 124a of face plate .124. The valve member 130 has arelatively wide port 132- adapted to continuously communicate a chamber139 within the valve member 130 with the chamber 123a of the basemember'115. According to the radial position of the valve member, thechamber 139 is either connected to chamber 123 by a narrow port 134 orto atmosphere through a vent port 138 in the valve head and vent slot127 on the external surface 124a. On over-speed, the clearance betweenthe This arrangement is basically the base and valve member ventschamber 139 to atmosphere through slot 132-. The ports 132 and 134 areseparated by an intermediate area 136 that blocks off the port until thevalve member has moved outwardly a given radial distance with respect tothe face plate 124, at which time the port 125 registers with port 134to communicate chamber 123 with chamber 139. The radially outwardmovement of the valve member 130 also closes the vent port 133 after agiven movement of the valve member. This arrangement of the valvingports is disclosed in detail in FIGURE 9. The length of ports may bevaried according to the amount of' fluid passage needed to operate thethrottle valve servo-motor.

It is realized that if a vacuum is used to operate the speed controlmechanism, the air will actually flow from the outlet tube 116 to theinlet tube 1%9; however, for simplicity, the speed control mechanism isbeing discussed as if the operating fluid has a pressure aboveatmospheric. The same modulating principle is present when vacuum froman engine manifold is used. To further define the fluid path, thechamber 123a is communicated to a passage by way of central openings144, 146 in a pair of drive shafts 149, 142. Passage 150 is locatedwithin a support rod block 148 and is communicated through passage 153in sleeve 152 on extension 151 of an output shaft 121 to the outlet tube116.

Slidably received on the outer surface of sleeve 152 is a spring plate169 that supports adjusting spring 166, control springs 164, andcounterweight spring 167. The

control springs 164, 165 are secured to parallel flat sur-' faces on thespring plate which arrangement is slightly different than the means forattaching the control springs in the previously discussed embodiment.Spring plate 169 is urged against a pair of adjusting screws 163 by acentral compression spring 161 and a pair of spaced compression springs162. Thus, valve member 130 may be adjusted with respect to surface 124aby the screws 153 or by nut 154. As in the other embodiment of thisinvention, the control springs 164, 165 control the movement and providethe resilient mounting for valve member 130 which, of course, has itscenter of gravity offset from axis x.

To vary the speed setting of the control mechanism, the

openings. Adjusting spring 166 abuts surface 187 to provide a changeablefulcrum for adjusting spring 166 which varies the speed setting as theplate 183 is reciprocated longitudinally. Lower flat surface 188contacts counterweight spring 167 in much the same manner. A hearing.

sleeve journals a control rod 182 which manually reciprocates theadjusting plate 189 along drive shafts 140, 142. In this embodiment ofthe speed control mechanism, a counterweight 168 is attached to spring167 in order to obtain dynamic balance of the rotating parts. Inoperation, this modification of the speed control mechanism functionsquite similarly to the embodiment of FIGURES 1-6. T here are someimportant differences, especially in the valving between the valve baseand the valve head and in the speed setting arrangement.

Referring again to FIGURE 7, the speed control mechanism is shown in theposition assumed when the vehicle is not moving. Means are provided tovent the servo-motor to atmosphere and in the embodiment the chamber123a, which usually has fluid of a modulated pressure, is vented to theatmosphere through ports 126,

132 and 138 and groove 127 as is indicated by the arrow. Thus, there isno pressure exerted upon the throttle controlling servo-motor. Until thespeed control mechanism is activated by a valve as discussed later, nopressure is introduced through tube 109. Upon activation of the controlmechanism, pressure preferably vacuum from the engine intake manifold,is introduced through the tube 109 and into chamber 123. However, thepressure cannot be communicated with chamber 139 because the port 125 isclosed by intermediate area 136. As the vehicle speed increases,assuming that the control mechanism is activated and chamber 123 ispressurized, the valve member 130 moves radially outwardly bycentrifugal force to close the atmospheric vent and open port 125. Thuspressure is communicated to chamber 139. The atmospheric vent defined byport 138 prevents this pressure from being directed into chamber 123auntil port 125 and port 134 are substantially aligned to direct apressurized fluid into chamber 139. With the ports 125 and 134 aligned,the maximum pressure is transmitted through the ports to open thethrottle valve and the speed con trol mechanism assumes control of thevehicle engine. This is a safety feature because without the atmosphericventing ports and the blocking area 136 the control mechanism could takeover operation of the engine before such control is desirable. If thespeed control mechanism were turned on while the vehicle is stopped andthe transmission is in neutral, the control mechanism would speed up theengine in an attempt to bring the vehicle to the speed to which thecontrol mechanism is adjusted, which would result in over speeding theengine. If the vehicle were in gear, the speed control mechanism wouldinadvertently start and accelerate the vehicle.

In FIGURE 10, the control mechanism is exerting a maximum force to openthe throttle. As the vehicle speed increases, the valve member 136 movesradially outwardly to restrict communication between ports 125 and 134.As the communication of these ports is restricted, the pressure withinthe chamber 123a is varied and the servo-motor tends to close the enginethrottle. According to the setting of the fulcrum plate 183, anequilibrium is reached whereby the vehicle speed is maintained constant.

FIGURE 12 shows the use of the speed control mechanism and its relationto various components within the vehicle. A servo-motor 2%, the functionof which has been previously mentioned, controls the movement ofdepending lost motion link 292 which engages pivotal control link 206.The servo-motor may be vented to give an improved response to variationsin pressure. Control link 2436 operates a butterfly valve 295 within anengine carburetor 294 by a suitable connection not shown in detail. Whenthe servo-motor is in its normal position, the link 262 is fullyextended and the butterfly valve 205 may be manually operated withoutinterference by the control link 202. When pressurized fluid, i.e.,vacuum, is introduced into the servo-motor 200, the link 202 is pulledupwardly against a control means such as a spring to open the butterflyvalve in accordance with the modulated pressure of the fluid within theservo-motor. The control link 2% is preferably biased into a valveclosed position so that it follows the movement of the link 202. Avacuum line 207 is communicated to the intake mani fold of the engineand terminates at a control valve 208. This valve 208 introduces vacuuminto line 269 connected to inlet tube 9 of the speed control mechanism211. The outlet tube 16 is connected by a line 21% to direct fluid at amodulated pressure from the speed control mechanism to the servo-motor209. The speed control mechanism is driven at a speed proportional tothe Vehicle speed by a line 213 from transmission 212. A power takeofffrom the speed control mechanism may be used to operate a device such asa speedometer 214. The valve 208 is operated by a manually controlleddevice 216 which is 1% schematically shown as a cam and electricalcontacts, however, any mechanical, electrical, hydraulic or pneumaticdevice may be used to open and close the valve 208. When the valve 208is opened and the speed of the vehicle is above a certain value, thespeed control mechanism 221 cuts in to maintain the vehicle speedsubstantially constant.

When the brakes of the vehicle are applied, it is no longer advantageousto control the speed of the vehicle. Thus, the valve 208 may be closedby a means 222 which is shown as a hydraulically operated electricalswitch; however, any suitable arrangement may be used. As the brake isdepressed, the valve 208 is disconnected and the butterfly valve is thencontrolled manually.

A variety of manually operated arrangements may be used tolongitudinally position adjusting plate 69 to vary the speed setting ofthe control mechanism. One of such arrangements 240 comprises a manuallyoperated cam 241 and a spring 232 which maintains the adjusting plate 69in contact with the cam. Of course, a Wide variety of devices may beused.

Even if the speed control mechanism is not turned on by opening valve268, it is possible to use the flyweight arrangement within the controlmechanism to close a pair of contacts which would light a signal 230. Ofcourse, the contacts must be insulated so that they are electricallyconnected only when speed reaches a predetermined value. The signal 230may be an electrically energized audible device such as a bell or abuzzer or a visual device such as a lamp.

The present invention has been described in conjunction with twostructural embodiments, but the scope of the invention is not to belimited thereby. The invention may take a variety of structuralembodiments without departing from the scope and spirit of the dependingclaims.

What is claimed as new is:

1. In a speed control mechanism for controlling the speed of a vehiclehaving a throttle controlled driving engine comprising a source ofpressurized fluid, a fluid operated throttle control device, and apressure modulating means responsive to the speed of a vehicle tomodulate the pressure of the fluid as it passes from the fluid source tothe throttle control device to control the throttle setting according tothe speed of the vehicle, the improvement comprising: said pressuremodulating means comprising a radially fixed base member connected tosaid fluid source and having a first control port, and a valve membermovably mounted on a frame rotatable about an axis at a speedproportional to the vehicle speed and said valve member having a secondcontrol port and'an outlet passage, means connecting said outlet passageof said valve member to said throttle control device, said valve memberhaving a center of gravity offset from said axis, resilient meansconnecting said valve member to said frame so said valve member isradially displaced against the resiliency of said resilient means inaccordance with the vehicle speed, said first control port substantiallyaligned with said second control port when the rotational speed of saidvalve member is at a first speed and said first control port and saidsecond control port being shifted radially from alignment as said valvemember shifts radially in accordance with the vehicle speed and supportmeans to maintain said valve member and said base member in close spacedrelationship at all times, said resilient support means comprising acantilever spring having a radially fixed end connected to said frameand a radially movable end connected to said valve member so that thecentrifugal force exerted on said spring by the valve member asthe speedof said vehicle incresaes causes said movable end to move radiallyoutwardly a-distance corresponding to the speed of the vehicle.

2. A speed responsive pressure modulating valve adapted for use in aspeed control mechanism for a vehicle driven by a throttle controlledengine, said valve comprising a frame rotatable about an axis at a speedproportional-to the speed of the vehicle, a base member mounted on saidframe and having a first and a second chamber, said first chamberconnected to a source of fluid having unmodu lated pressure and saidsecond chamber connected to a control device for said throttle, saidbase member having an external surface, a first port connected to saidfirst chamber and a second port conected to said second chamber, saidfirst and second ports extending through said external surface, a ventgroove in said external surface, a valve member mounted on said frameand having an intermediate chamber with a larger outlet port, a smallerinlet port, an intermediate area between said larger and said smallerports, and a vent port, said base member and said valve member rotatingwith said frame, said valve member having a center of gravityoifset fromthe axis of rotation of said frame and a resilient means which allowsthe valve member radial displacement with respect to said base member inresponse to changes in the rotational speed of said frame, said largerport opposite said second port to communicate said second chamber withsaid intermediate chamber at all times, said intermediate area closingsaid first port While said vehicle speed is below a predetermined value,when said vehicle speed is below this predetermined value, the externalsurface .of said base member closes said smaller port and said vent portcommunicates with said groove to vent the intermediate chamber toatmosphere, at a vehicle speed above this predetermined value, saidsmaller port coacts with said first port to modulate the pressure of thegas in said second chamber in accordance with the radial displacement ofsaid valve member and said vent port is closed by said external surfaceof said base member, and a support means to maintain said valve memberclose to but spaced from the external surface of said base member duringradial displacement of said valve member 3. in a speed control mechanismfor controlling the speed of a vehicle having a throttle controlleddriving engine comprising a source of fluid having unmodulated pressure,a fluid operated control device for changing the setting of the throttlein response to a modulated fluid pressure, and a vehicle speedresponsive modulating means between said source and said control device,the improvement comprising: a firststationary frame and a second framesaid second frame journaled within said first frame and rotatable aboutan axis, said first frame comprising a first end plate and a second endplate, each of said end plates having an inner fluid chamber, meanscommunicating the inner chamber of the first end plate to said sourceand means communicating the inner chamberof said second end plate tosaid fluid control device, a base member mounted on said second frameand having a passage communicated to the inner chamber of said first endplate, a spring plate mounted on said second frame and having a passagecommunicated to the inner chamber of said second end plate, said springplate and said :base member secured in fixed, spaced relationship toeach other by at least one drive shaft, a valve member having a centerof gravity offset from the axis of rotation of said second frame androtatable withsaid second frame, spring means joining said valve memberto said spring plate so said valve member moves radially outwardly asthe speed of said second frame increases, support means to maintain saidvalve member close to, but spaced from, said base member, meanscommunicating said valve member to said inner chamber of said second endplate, a control port in said base member and a control port in saidvalve member, said control ports lying on said axisof rotation and beingsubstantially aligned at relatively low speeds to move said throttletoward an open position and said control ports being shifted fromalignment as said valve member moves radially in response to an increaseof the rotational speeds of said second frame to move said throttletoward a closed position.

4. The improvement as defined in claim 3 where-in said meanscommunicating said valve member to said inner chamber of said second endplate comprises a flexible tube extending from said valve member to saidpassage in said spring plate.

5. The improvement as defined in claim 3 wherein said meanscommunicating said valve member to said inner chamber of said second endplate comprises a port in said valve member in substantially continuousalignment with an inlet port in said base member, said inlet portconnected to anintermediate passage in said base member, and a passagethrough said drive shaft from said intermediate passage to said passagein said spring plate.

6. A speed sensitive valve adapted to control the pressure of fluid to aservo-motor, said valve comprising a base member and, a valve member,said valve member being rotatable about an axis and having a center ofgrav- 'ity offset from said axis, each of said members having a largearea surface substantially perpendicular to said axis and slightlyspaced from each other, said surfaces movable with respect to each otherin a direction perpendicular to said axis, each of the surfaces having acontrol port adapted to shift into and out of alignment as the valvemember rotates and is moved radially by centrifugal force, means formaintaining saidsurfiaces in close, spaced relationship as they movewith respect to each other a resilient means yieldably opposing saidradial movement, and a first means to vent the servo-motor to atmospherewhen said centrifugal force is below a predetermined value, and a secondmeans to close said first means when said centrifugal force equals saidvalue.

7. In :a speed control mechanism for controlling the speed of a vehiclehaving a throttle controlled driving engine comprising a source ofpressurized fluid, a fluid operated throttle control device, and apressure modulating means responsive to the speed of a vehicle tomodulate the pressure of the fluid as it passes from the fluid source tothe throttle control device to control the throttle setting according tothe speed of the vehicle, the improvement comprising: said pressuremodulating means comprising a radially fixed base member connected tosaid fluid source and having a first control port, and a valve membermovably mounted on a frame rotatable about an axis at a speedproportional to the vehicle speed and said valve member having a secondcontrol port and an outlet passage, means connecting said outlet passageof said valve member to said throttle control device, said valve memberhaving a center of gravity offset from said axis, resilient meansconnecting said valve member to said frame so said valve member isradially displaced against the resiliency of said resilient means inaccordance with the vehicle speed, said first control port substantiallyaligned with said second control port when the rotational speed of saidvalve member is at a first speed and said first control port and saidsecond control port being shifted radially from alignment as said valvemember shifts radially in accordancewith the vehicle speed and supportmeans to maintain said valve member and said base member close to butspaced from each other at all times, said support means comprising apair of substantially parallel links having first ends connected to saidvalve member at spaced points and having second ends connected to saidframe on opposite sides of the rotational axis of said frame.

8. The improvement as defined in claim 7 having means for adjusting theresiliency of said resilient means to change the amount of radialdisplacement of said valve member for any given vehicle speed, saidadjusting means comprises an adjusting spring having a radially fixedend connected to said frame remote from said valve member and a radiallymovable end connected to said valve member and a movable fulcrum, saidmovable fulcrum contacting said spring between its ends to determine theeffect of'said adjusting spring on the radial movement of said valvemember.

9. In a speed control mechanism comprising a first valve member and asecond valve member, each of said valve members being rotatable about anaxis, said second valve member having a center of gravity offset fromsaid axis whereby rotation of said members about said axis causes saidmembers to shift with respect to each other in a direction transverse tosaid axis, resilient means to control the transverse displacement ofsaid members for a given speed, means for adjusting the resiliency ofsaid resilient means to change the rate of transverse displacement ofsaid members, the improvement comprising: said adjusting means includingan adjusting spring having an end radially fixed with respect to saidfirst valve member remote from said second valve member, said springhaving a radially movable end connected to said second valve member anda movable fulcrum, said fulcrum contacting said spring between its endsto determine the effect of said adjusting spring on the radialdisplacement of said valve members.

10. In a speed control mechanism comprising a first valve member and asecond valve member, each of said valve members being rotatable about anaxis, said second valve member having a center of gravity offset fromsaid axis whereby rotation of said members about said axis causes saidmembers to shift with respect to each other in a direction transverse tosaid axis, resilient means to control the transverse displacement ofsaid members for a given speed, means for adjusting the resiliency ofsaid resilient means to change the rate of transverse displacement ofsaid members, the improvement comprising: said adjusting means includingan adjusting spring having an end radially fixed with respect to saidfirst valve member remote from said second valve member, said springhaving a radially movable end adapted to contact said second valvemember and move said valve member radially inward and a movable fulcrum,said fulcrum contacting said spring between its ends to determine theeffect of said adjusting spring on the radial displacement of said valvemembers.

11. In a speed control mechanism comprising a first valve member and asecond valve member, each of said valve members being rotatable about anaxis, said second valve member having a center of gravity offset fromsaid axis whereby rotation of said members about said axis causes saidmembers to shift with respect to each other in a direction transverse tosaid axis, resilient means to control the transverse displacement ofsaid members for a given speed, means for adjusting the resiliency ofsaid resilient means to change the rate of transverse dis placement ofsaid members, the improvement comprising: said resilient means includingan adjustable spring having an end radially fixed with respect to saidfirst valve member remote from said second valve member, said springhaving a radially movable end arranged to bias said second valve memberradially inward, and said adjusting means including a movable fulcrum,said fulcrum contacting said spring between its ends to determine theeffect of said spring on the radial displacement of said valve members.

12. A speed control mechanism for controlling the fiow of fluid in aline in response to the speed of a rotating shaft comprising a fixedframe, a second frame rotatably journaled with respect to said fixedframe and arranged to be rotated in timed relationship with the speed ofsaid rotating shaft, a first valve member on said second frame, secondvalve member shiftably mounted on said second frame, unbalanced massmeans mounted for rotation with said second frame arranged to shift saidsecond valve member with respect to said first valve member responsiveto the centrifugal force produced by rotation of said second frame,valving means carried on said first and second valve members adapted tocontrol the flow of fiuid through said line responsive to the relativeposition of said valve members, spring means carried on said secondframe arranged to produce a biasing force in opposition to thecentrifugal force produced by said unbalanced mass means, adjustingmeans movable to vary the biasing force of said spring means, andcontrol means for moving said adjusting means during rotation of saidsecond frame and including a non-rotatable member and bearing meanscoaxial with the axis of rotation of said second frame interconnectingsaid non-rotatable member and said adjusting means.

13. A speed control mechanism for controlling the flow of fiuid in aline in response to the speed of a rotating shaft comprising a fixedframe, a second frame mounted to rotate with respect to said fixed frameand in timed relationship with the speed of said rotating shaft, a firstvalve member on said second frame, a second valve member shiftablymounted on said second frame, unbalanced mass means mounted for rotationwith said second frame and arranged to shift said second valve memberwith respect to said first valve member responsive to the centrifugalforce produced by rotation of said unbalanced mass means by said secondframe, valving means carried on said first and second valve members forcontrolling the flow of fluid through said line responsive to therelative position of said valve members, spring means carried on saidsecond frame and arranged to produce a biasing force in opposition tothe centrifugal force produced by said rotating unbalanced mass means,and adjusting means for adjusting the biasing force of said springmeans, said adjusting means including an adjusting member movable alongthe axis of rotation of said second frame and rotatable therewith, saidadjusting member coacting with said spring means to change the biasingforce of said spring means in accordance with the axial position of saidadjusting member, and a movable member on said fixed frame for adjustingthe axial position of said adjusting member while it is rotating.

14. A speed control as defined in claim 13 wherein said spring means isa spring extending axially of said second frame and said adjustingmember is a fulcrum movable axially along said spring.

15. A speed control as defined in claim 14 wherein said movable memberhas a bearing surface engaging said rotating adjusting member andincluding means for moving said movable member in a direction axial ofsaid second frame.

References Cited by the Examiner UNITED STATES PATENTS 1,550,567 8/25Oliver 13756 X 2,081,466 5/37 T-arisien 137-56 2,779,582 1/57 Hopper etal. 13756 X 2,935,076 5/60 Larges et al. 137-56 3,023,761 3/62 Greenlees137-56 FOREIGN PATENTS 803,629 4/51 Germany. 909,655 4/ 54 Germany.

OTHER REFERENCES Akt. G. Kuhnle, Kopp and Kausch (Germany) K 15, 677,Feb. 9, 1956.

A. HARRY LEVY, Primary Examiner.

1. IN A SPEED CONTROL MECHANISM FOR CONTROLLING THE SPEED OF A VEHICLEHAVING A THROTTLE CONTROLLED DRIVING ENGINE COMPRISING A SOURCE OFPRESSURIZED FLUID, A FLUID OPERATED THROTTLE CONTROL DEVICE, AND APRESSURE MODULATING MEANS RESPONSIVE TO THE SPEED OF A VEHICLE TOMODULATE THE PRESSURE OF THE FLUID AS IT PASSES FROM THE FLUID SOURCE TOTHE THROTTLE CONTROL DEVICE TO CONTROL THE THROTTLE SETTING ACCORDING TOTHE SPEED OF THE VEHICLE, THE IMPROVEMENT COMPRISING: SAID PRESSUREMODULATING MEANS COMPRISING A RADIALLY FIXED BASE MEMBER CONNECTED TOSAID FLUID SOURCE AND HAVING A FIRST CONTROL PORT, AND A VALVE MEMBERMOVABLY MOUNTED ON A FRAME ROTATABLE ABOUT AN AXIS AT A SPEEDPROPORTIONAL TO THE VEHICLE SPEED AND SAID VALVE MEMBER HAVING A SECONDCONTROL PORT AND AN OUTLET PASSAGE, MEANS CONNECTING SAID OUTLET PASSAGEOF SAID VALVE MEMBER TO SAID THROTTLE CONTROL DEVICE, SAID VALVE MEMBERHAVING A CENTER OF GRAVITY OFFSET FROM SAID AXIS, RESILIENT MEANSCONNECTING SAID VALVE MEMBER TO SAID FRAME SO SAID VALVE MEMBER ISRADIALLY DISPLACED AGAINST THE RESILIENCY OF SAID RESILIENT MEANS INACCORDANCE WITH THE VEHICLE SPEED, SAID FIRST CONTROL PORT SUBSTANTIALLYALIGNED WITH SAID SECOND CONTROL PORT WHEN THE ROTATIONAL SPEED OF SAIDVALVE MEMBER IS AT A FIRST SPEED AND SAID FIRST CONTROL PORT AND SAIDSECOND CONTROL PORT BEING SHIFTED RADIALLY IN ACCORDANCE WITH THEVEHICLE SPEED AND SUPPORT MEANS TO MAINTAIN SAID VALVE MEMBER AND SAIDBASE MEMBER IN CLOSE SPACED RELATIONSHIP AT ALL TIMES, SAID RESILIENTSUPPORT MEANS COMPRISING A CANTILEVER SPRING HAVING A RADIALLY FIXED ENDCONNECTED TO SAID FRAME AND A RADIALLY MOVABLE END CONNECTED TO SAIDVALVE MEMBER SO THAT THE CENTRIFUGAL FORCE EXERTED ON SAID SPRING BY THEVALVE MEMBER AS THE SPEED OF SAID VEHICLE INCREASES CAUSES SAID MOVABLEEND TO MOVE RADIALLY OUTWARDLY A DISTANCE CORRESPONDING TO THE SPEED OFTHE VEHICLE.